Ms Hambleton, whose older sister Maxine was among the 21 killed by the blasts in two busy city venues in 1974, was taking part in a BBC Radio 4 Today discussion with Mr Conway.

He said that while the carnage was "appalling on every level" and "immoral", the fact that warnings were reportedly attempted - but thwarted by vandalised phone boxes - reduced the blame.

"I take the view that appalling and all as the bombs were, the volunteers who carried them out were relatively blameless in that their only fault was that they carried out the instructions of their commander," he told the programme.

"Their only fault was that they didn't - and this would have been elementary, I was trained in bomb planting myself and planted a few in my time - in advance check that they had working phone boxes and a back-up in case of difficulty.

"I don't view IRA volunteers as murderers; I view them as people who participated in a just war."

He said there was "no prospect of convictions" because there was "simply no evidence" and it would be very hard to extradite individuals to the UK from Dublin.

"The only way that there could be convictions for the Birmingham bombs would be if one or more of the bombers were to present themselves to the UK police station and make full confessions. I don't believe that will happen."

His words met a furious response from Ms Hambleton, who said he was "delusional" and gave a graphic description of the injuries suffered by victims.

"Men - or women, we don't know - planned, prepped, put together bombs, walked into two pubs and then claim that it was an accident? I have never heard such a load of utter rubbish," she said.

"How dare he be on the other end of the line and make such claims?

"It was 'an accident', it was 'approved', he doesn't consider them to be murderers?

"I wonder if one of his kids was killed beyond description - when all their skin has literally been stripped off their body, they've got no legs, they've got no arms, you can't recognise them by their face because their injuries are such that they've already been partially cremated - how dare he make such harrowing and horrendous statements over the airwaves.

"If they were soldiers they would have principles and discipline. Where was their discipline? They denied doing it in the first place, which showed they knew they'd done wrong.

"It just shows how gutless they are because if they had any kind of morals or humanity they would actually do exactly what Kieran Conway has said, and walk into the local police station and put their hands up and say 'I did it and I'm proud I did it and I'm coming in to admit to what I've done'."

She told the programme she had deliberately avoiding having children because she would not be able to bear the trauma of losing one.

"But we have got to fight for future generations because otherwise anyone can kill anyone and never have to fear about facing the law and doing time for the crimes they commit.

"If we don't fight for truth, justice and accountability then what we are basically allowing is for any future terrorist group to come to any of our great cities and kill with impunity.

"If we don't fight - and the authorities can't be bothered - as a society we are going to allow anarchy to rule okay."